The police operation was launched in 21 provinces across Turkey, the state-run news agency reported.

Ankara says cleric Fethullah Gulen, who has lived in the United States since 1999, was behind the abortive putsch in July 2016. Gulen has denied involvement.

More than 50,000 people have been jailed pending trial for alleged ties to Gulen’s movement and some 150,000 people have been sacked or suspended from jobs in the public and private sectors for the same reason.

Some of Turkey’s Western allies and rights groups have expressed concern about the crackdown and suspect the government has used the coup as a pretext to quash dissent.

The government says the purges are necessary due to the gravity of the threats it has faced since the failed putsch, in which more than 240 people were killed.